[artwill872]

I was told that MnO4 is a polyatomic ion with the name permanganate and that MnO is a molecular compound with the name Manganese(II) oxide.

I initially thought MnO would have the name "hypomanganite," since it seemed similar to the polyatomics with chlorine and an oxygen (perchlorate, chlorate, chlorite, hypochlorite). Why isn't this the case?

Also, Mn should be considered a transition metal according to the little bit that I know. Why isn't MnO at least an ionic compound?

[rabolisk]

MnO4^- is permanganate. MnO isn't negatively charged, so it is not an anion. Basically, they are named what they are named because they are what they are (an ion in the former and a neutral compound in the latter).

For a more complex answer, Mn can have many oxidation states, but the most common are +2, +4, and +7. Oxygen usually has an oxidation state of -2. Convince yourself that putting together Mn and 4 O will result in -1. Similarly convince yourself that one Mn and one O results in neutral charge.

MnO is an ionic compound.